The incongruous tombstone of a Canadian mujahid stands on a lush hill at the edge of Utamysh, a village in southern Russia’s Dagestan region, within reach of the salty breeze that comes off the Caspian Sea. The riddles of the life it demarcates — the ones U.S. investigators are now reportedly studying in connection to the Boston Marathon bombings — start to become apparent even from the stone’s inscription.

For one, the name says William Plotnikov, an unusual fusion of English and Russian that hints at his family’s move from Siberia to the West. Then there is the stone’s Islamic crescent moon and star, suggesting a conversion to Islam — as do the weeds that grow over the swollen mound of earth. (In local Muslim tradition, it is forbidden to pluck fresh weeds from a grave site, because they are thought to help the dead atone for sins.) And then there are the grim dates: born in Russia on May 3, 1989, Plotnikov was killed in a shootout with Russia’s counterterrorism forces on July 14, 2012. He was 23.

For American investigators, the date of Plotnikov’s death has reportedly been of particular interest. Just a few days after Plotnikov was killed in Dagestan, Tamerlan Tsarnaev, the prime suspect in the Boston bombings, left the region and went back to the U.S. in an apparent hurry. He did not even wait to pick up his new Russian passport, which his parents claim to be the reason he came to Russia in the first place.

The parallels between Plotnikov’s and Tsarnaev’s biographies are also striking. Both their families have roots in predominantly Muslim regions of Russia — Plotnikov’s mother is Tatar; Tsarnaev’s parents are from the North Caucasus. Both of them became avid amateur boxers in North America after their families emigrated there. Both of them embraced radical Islam while grasping around for an identity in their adopted homes. Both of them came to Dagestan to explore their faith. And both of them were in Dagestan between January and July last year, when Plotnikov had already joined an Islamist militant group and Tsarnaev was attending services at a radical mosque.

There is no clear evidence to show that the two of them met or knew each other. But on Saturday, Russia’s Novaya Gazeta, an independent newspaper with a strong reputation for investigative reporting, wrote that Tsarnaev first drew the attention of Russia’s FSB security service because of his connection to Plotnikov. In early 2011, the FSB’s counterterrorism agents detained Plotnikov as an “adherent of radical Islam” in Dagestan, and Tsarnaev’s name came up during the interrogation, Novaya Gazeta reported. The FSB then sent its first request to the FBI asking for information on Tsarnaev, who was then living in the U.S. In response, the FBI said it interviewed Tsarnaev in Boston but found no links to terrorist activity. U.S. investigators are now trying to determine whether the two men met in Dagestan, the New York Times reported on Sunday, citing a law-enforcement official.

On Friday afternoon in the village of Utamysh — home to about 3,000 people, most of them ethnic Kumyks — TIME showed photos of Tsarnaev to the family that Plotnikov lived with, and after studying the images they all shook their heads without recognizing him. “I don’t know,” says Maryam, the woman who said she was “like a mother” to Plotnikov in Dagestan. (She asked that her last name not be published, fearing that she would be hounded by investigators and the press.) “Maybe they knew each other through boxing. But I never saw him here,” she says of Tsarnaev.

Maryam said Plotnikov fell in with the local Islamist insurgents after attending services at a local mosque that espoused a fundamentalist brand of Islam called Salafism, which calls for an Islamic caliphate governed by Shari‘a. “All of those boys died with him,” she says. In a statement released in July, the Russian security services said they had cornered a group of militants in the forests around Utamysh. In the ensuing firefight, which lasted much of the early morning of July 14, seven militants were killed, including the leader of a local militant group named Islam Magomedov. Plotnikov was among the dead, and a local jihadist website later mourned him as a martyr.

The local police chief in Utamysh, Murtuzali Abdurakhmanov, confirmed to TIME that Plotnikov had been a member of a terrorist group in the village and was killed in a counterinsurgency operation. “Everybody knew him as the Canadian,” he says in an interview at the local police station. “We don’t get a lot of outsiders around here, so his story made a lot of noise.” But Abdurakhmanov did not recognize the name or the photographs of Tsarnaev. “We’d probably have heard if an American had come around to see him.”

When police brought Plotnikov’s body back to the village from the forest in July, the congregants at the mosque washed it and prepared it for burial, Imam Arslangerey, of the mosque where Plotnikov worshipped, tells TIME. “It was not bloated like you would expect after that much time had passed. He looked like he was sleeping.” A local businessman, he says, had donated the money for his gravestone, which was set apart from the other graves at the very end of the cemetery that creeps up a hill on the edge of the village, overlooking a pasture where locals graze their cows. “He was a member of our community,” says the imam. “He was a Muslim. So whatever he may have been involved with, he deserved a traditional burial.”

According to a detailed report in Canada’s National Post last year, Plotnikov had converted to Islam in 2009 while living with his parents outside Toronto. Only three years later, he was killed as an insurgent in the mountains of Dagestan. “How can the mind of a person be changed in such a short period of time?” his father Vitaly Plotnikov asked the National Post. The same question now hovers around the fate of Tsarnaev, who embraced a radical version of his faith less than three years before the Boston bombings.

Citing its sources in the Russian security services, Novaya Gazeta also reported that Tsarnaev had met multiple times in Dagestan with a suspected Islamist named Mahmud Mansur Nidal, an 18-year-old with mixed Kumyk and Palestinian ancestry. Russian operatives had been watching Nidal for a year as a suspected recruiter for local Islamist groups, according to Novaya Gazeta. That was why the FSB sent further requests to U.S. law-enforcement agencies after Tsarnaev’s alleged meetings with Nidal in Dagestan last year. Nidal was killed in a shootout with Russian police in May 2012, about two months before Tsarnaev went back to Boston from Dagestan.

The U.S. investigation into the bombings of April 15 now seems to have turned to the role Tsarnaev’s contacts in Dagestan played in his radicalization. In the coming days and weeks, it seems inevitable that the sleepy, dirt-road village of Utamysh will also start getting a lot more foreign visitors. At the police station, which is no more than a one-room hut with a few rickety chairs, police chief Abdurakhmanov prepared for this prospect with the typical nonchalance of the locals. “Maybe I’ll go on vacation,” he says.